The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
A multi-speed automatic transmission uses frictional clutches having friction surfaces for example as lock-up clutches to temporarily lock a torque converter to a transmission input shaft, and clutches and brakes to change gear ratios during transmission shifting operations for both forward and reverse gear drives. Known clutch assemblies provide friction surfaces on multiple friction plates that engage multiple reaction plates when hydraulic pressure is applied to the clutch assembly. Known clutch assemblies use spline connections to individually couple the reaction plates and the friction plates to transmission structure or to components of the transmission. The spline connections, however provide only limited horizontal displacement.
When the clutch assembly is not engaged by hydraulic pressure it is desirable to maintain clearance between the friction surfaces and the reaction plates to reduce friction induced heat, friction surface wear, and the associated degradation of fuel economy. The limited horizontal displacement allowed by spline connections may not allow sufficient clearance between these components to be maintained and therefore may often induce heat, friction, and degraded fuel economy.
Thus, while current automatic transmission clutch assemblies achieve their intended purpose, there is a need for a new and improved device and method for reducing or eliminating splined clutch assemblies thereby allowing greater horizontal movement of the reaction plates to improve clutch assembly design.